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Flashcards in test #18 4.6 Deck (131)
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which antigen on e.coli is the major virulent determinant for meningitis

K-1 antigen (capsular). inhibits complement and phagocytosis.


how does e.coli lead to meningitis

invade blood stream from nasopharynx or GI tract. travel hematogenously to meninges.


what rxn results from a beesting?

local allergic rxn: type 1 HSR. direct crosslinking of IgE on mast cells & basphils --> histamine, proteases, heparin, leukotrienes, and prostaglandins --> wheal (urticaria: erythematous papule or plaque w/ central pallor)


TNF-alpha made by..

made by macrophages and mast cells. signals for apoptosis of tumor cells & activation of inflammatory cells (like CD4+ T lymphocytes, neutrophils, fibroblasts, endothelial cells, and hematopoietic cells)


name 2 conditions w/ elevated TNF-alpha. rx?

in many inflammatory conditions: rheumatoid and psoriatic arthritis. can be elevated in type IV HSR

rx: inflixamab and entanercept


inflixamab and etanercept?

humanized anti-TNFalpha immunolobulins that reduce inflammation in rheumatoid and psoriatic arthritis -- prevent induction of inflammation


Th1 vs. Th2 immune responses

Th1, secrete IL-2 induces macrophage and cytotoxic T-cell rxn

Th2, secrete IL-4, induces humoral immunity.


anal canal extends from __ to __? upper & lower canal?

extends from perineal flexure (anorectal junction) to perianal skin (anal verge). divided to upper and lower canal.

upper canal: above pectinate line: hindgut
lower canal: invagination of surface ectoderm.

junction between these canals -- closed during embryonic life by anal membrane at level of pectinate line.


imperforate anus? associated w.?

spectrum of disorders w/ abnormal development of anorectal structures.

MOST OFTEN associated w. GENITOURINARY TRACT MALFORMATIONS: urorectal, urovesical, or urovaginal fistulas.

can see meconium discharge from urethra or vagina

also: renal agenesis, hypospadias, epispadias, bladder extrophy

other congenital abnormalities w/ imperforate anus VACTERL:
vertebral defects, anal atresia, cardiac anomalies, tracheoesophageal fistula, esophageal atresia, renal anomalies, limb anomalies


VACTERL syndrome?

vertebral defects, anal atresia, cardiac anomalies, tracheoesophageal fistula, esophageal atresia, renal anomalies, limb anomalies.

much less common than isolated urogenital anomalies associated w/ imperforate anus.


if there is a 95% confidence interval that a value falls between 2 numbers..

there is at least a 5% chance the value falls outside this range, some equal to p value (probability that results obtained were due to chance alone)


hawthorne effect

tendency of a study population to affect an outcome due to KNOWLEDGE OF BEING STUDIED


pygmalion effect

describes researcher's belief in the efficacy of treatment that can potentially affect the outcome


schilling test: purpose of intramuscular injection of cobalamin w/ radiolabeled cobalamin?

ensure that radiolabeled will be excreted in urine for measurement.

high B12 in urine -- B12 deficiency.
low -- either instrinsic fxr or absorption problem.
low post administration of intrinsic factor -- intestinal malabsorption


causes of intestinal malabsorption of B12 (3)

pancreatic insufficiency, intestinal bacterial overgrowth, ileal disease


3 rx for acute gouty arthritis

(1) 1st line: NSAIDs (2) colchine and (3) glucocorticoids


impt side effects of colchines (3)

nausea, abdominal pain, diarrhea


hepatic encephalopathy

REVERSIBLE decline in neurologic function precipitated by hepatic damage


how does ammonia enter circulation

via GI tract; enterocytic catabolism of glutamine and bacterial catabolism of dietary protein in colon --> portal circulation to liver for detox into urea.


precipitants of hepatic encephalopathy (w/ underlying liver cirrhosis)

stressors that alter ammonia balance: GI bleed (hematemesis), hypovolemia, hypokalemia, metabolic alkalosis, hypoxia, sedative usage, hypoglycemia, infxn


rx: for hyperammonia

administer continuous disaccharide (lactulose): bacterial action on lactulose results in acidification of colonic contents -- convert absorbable ammonia into nonabsorbable ammonium (ammonia trap)


accumulation of BUN can indicate what 3 things?

(1) renal failure (2) heart failure (3) dehydration


describe neuropathy in diabetes (3)

(1) symmetric peripheral neuropathy (2) mononeuropathy (3) autonomic neuropathy


which CN is most common affected in diabetes? what type of injury? presentation

CN III; ischemic. note somatic / parasympathetic -- diff blood supplies. diabetic neuropathy.

affects SOMATIC -- ptosis w/ down & out gaze. accomodation in tact


nerve compression vs. diabetic ischemic injury to CNIII

nerve compression: both SOMATIC and parasympathetic; ptosis, down & out gaze, fixed dilated pupil, no accomodation

nerve ischemia: SOMATIC, ptosis w/ down & out gaze


somatic component of CNIII works on? parasympathetic component?

somatic: (1) extraocular muscles: inferior, superior, medial, inferior oblique. (2) levator palpebrae

parasympathetic: sphincter of iris & ciliary muscle


how can CN III be compressed (2)

(1) PComm aneursym (2) transtentorial herniation


describe hemosiderin

hemoglobin-derived marker of iron accumulation.

golden-yellow brown pigment that may appear in either granular or crystalline form.

aggregation of ferritin micelles


melanin formed when..

tyrosinase converts tyrosine to dihydroxyphenylalanine


why is right main bronchus more prone to foreign body aspiration?

(1) larger diameter (2) shorter (3) orientaed more vertically than left